When I had it boot with "24Gb (16Gb Usable)" it only showed 16Gb in the BIOS, I have it running with 20 right now - but the system acts kinda sluggish for some reason... It also gets REALLY hot, the system only has 1 120mm fan blowing in - I couldn't even run OCCT because when it was under 100% load it peaked at 82C before it started testing.